Aseptic filling unit for packing machines for longlasting products with fluid behaviour

Abstract

 For the manufacture of packing containers, and the packing inside said containers of long-lasting products with fluid behaviour, such as liquids, semi-liquids or products containing solid particles, the product delivering and metering devices are an integrant part of the packing machine and condition and influence the structure and the operating way thereof. An asepticfiliing unit according to the present invention solves said problems, in that it is a modular element interposed between the packing machine and the product feeding line, and can be isolated from both of them.

Description

[0001] The present invention relates to an aseptic filling unit, in particular for packing machines for long-lasting liquid, semi-liquid and/or solid particle containing products with fluid behaviour, such unit being absolutely aseptic, with metering control, easily replaceable and washable, and whose type of metering unit can be easily varied, without thereby significantly altering the working cycle of the machine.

[0002] It is generally desirable in the packing industry, to provide types of packings, packing processes and related equipment, which make it possible to pack different types of food products, so as to preserve as far as possible the original structure of the machinery, and the operating characteristics thereof.

[0003] The processing of liquid or semi-liquid food products to the purpose of conferring to them characteristics of long-life at room temperature and within suitable containers, presupposes a sterilization carried out e.g. by means of a so-called "UHT" (ultra-high temperature) plant, i.e. through a step of heatinry to 135-150°C, a dwell step at this temperature and a step of cooling to about 20°C with the subsequent delivery into the main distribution line to the aseptic packing machines. For the sterilization then of said machines and plants in case of packing of long-lasting products, an operation cycle starting with the chemical washing of the components which will come into contact with the product is carried out.

[0004] In particular, the product delivery regulation and level control device must be washed, which is usually placed at the end of the delivery pipe placed inside the tube of packing material which is being forced. For such an operation to be made possible, the said device is usually dismantled, with consequent time and production losses.

[0005] Moreover, regulation devices positioned dipped inside the product within the tube of packing material being formed, do not seem particularly suitable and universal with the varying of the density of the product to be packed, especially if they operate on the basis of hydrostatic or hydrodynamic principles, thus being it necessary to replace and fit them to the liquid, semi-liquid products, and to the presence of solid particles.

[0006] A purpose of the present invention is to provide an aseptic filling unit independent of the packing machine, and of the delivery line of the product to be packed.

[0007] Another purpose is to have a packing unit aseptic and easily washable and sterilizable even when inside the main distribution line a sterile product flows.

[0008] Another purpose is to make it possible to carry out a rather precise metering of the product contents within the single packing produced.

[0009] Another purpose is that the metering unit of said filling unit be suitable to be easily replaced by another, so as to make it more suitable to the product being processed and packed, without thereby substantially influencing the structure and the operation of the packing machine.

[0010] These and further purposes according to the present invention are achieved by providing an unit for the aseptic filling of long-lasting products with fluid behaviour into containers, for packing machines of the type wherein a pipe feeds said product, outcoming from a sterilization unit, into said containers, on the machine means for sealing the said containers being provided, characterized in that it is positioned between said product feed pipe and said product sterilization assembly, it being substantially constituted by a couple of valve groups, between which a unit functionally useful to the filling thereof connected by related pipes is inserted.

[0011] Preferably said unit functionally useful to the filling is a metering unit.

[0012] In a preferred embodiment, such a sterilization assembly is centralised and said unit is inserted in a branched line of a centralized line connected to said sterilization unit to the purpose of feeding a plurality of packing machines, a pump being provided for circulating the product in said line.

[0013] Advantageously, at least one of said valve groups is connected through a pipe to washing units, relating interrupting means being interposed.

[0014] The structural and functional characteristics and the advantages of a unit according to the present invention will be better understood from an exemplifying not limitative preferred embodiment thereof, referred to the related schematic drawings, in which:

Fig. 1 shows the scheme of a packing line with a plurality of aseptic filling units and machines inserted therein.

Fig. 2 shows in principle the conversion of a web-like packing material and the filling of container packings in a packing machine provided in a packing line,

Fig. 3 shows a schematic section of a filling unit according to the present invention in production stage,

Fig. 4 shows the section of the unit of Fig. 3 in preheating and/or sterilization stage, and

Fig. 5 shows the section of the unit of fig. 3 in non-aseptic chemical washing stage.

[0015] With reference to fig. 2, a packing machine generally indicated with 1, is of a general type previously known, which converts web-like packing material into individual packing containers. The packing material is of the laminate type, generally comprising a central carrier layer of paper, which is coated on both sides with thin layers impermeable to the liquid, made of thermoplastic material, e.g., of polyethylene. The packing laminate web is provided with crease lines to the purpose of facilitating the folding and conversion thereof into finished packing containers, and is supplied to the packing machine 1 in the form of a roll 2 which is suspended in such a way, as to be capable of rotating in the suitable section of the packing machine. From the storage roll the web of packing material 3 travels through a certain number of guide rollers 4 up to the upper part of the machine, where it is sterilized by known methods. After having been sterilized, the web travels on a reversal roller 5 for continuing travelling thereafter essentially vertically downwards, through the packing machine, in a sterile closed chamber (not shown).

[0016] With the aid of various folding and forming elements 6, 7, positioned along the travelling path of the web of material 3, the web of packing material 3 is subsequently tubularly shaped in a known manner during its run downwards, so as to obtain a tube of packing material 8 with a longitudinal liquid-tight seal, carried out by a sealing unit 9 which can operate on the basis of different principles. Simultaneously to the forming of the tube of packing material, the product to be packed is delivered to fill the lower portion thereof through one or more feeding pipe(s) 10, this or these pipe(s) being introduced through the upper - open - end of the tube of packing material, up to a suitable depth. The delivery pipe therefore extends essentially concentrically downwards through the tube of packing material, and opens at a short distance above the lover end.

[0017] At a certain distance under the delivery pipe 10, forming and sealing jaws 12, 13 ar positioned on both sides of the packing material tube 8 to act, cooperating as pairs with each other, on the tube of packing material 8. Said jaws are positioned in such a way, as to seal the tube of packing material at similar intervals along sealing zones.

[0018] By means of a series of combined movements, as the result, a packing container 14 is obtained in a formed shape and separated from the tube of packing material. After that the separation has taken place, the packing container 14 is made travel further on by means of a conveyor (not shown) to the purpose of continuing the processing and the final shaping thereof, so as to produce a packing container of the desired shape (in this case of parallelepipedon shape).

[0019] The pipe 10 of delivery and/or load of the product to be packed is connected e.g.(fig. 1) to a centralized product-distribution line or pipe 11, fed with sterilized product from a centralized sterilizer 15 or tank with the aid of a pump 16.

[0020] Said line 11 1 (fig. 1) serves e.g. a series of packing machines and related filling units 17 and returns to the tank 15, into which from the outside raw product is fed.

[0021] Between the single packing machine 1 and the centralized line 11 a filling unit according to the present invention is interposed, generally indicated with 17.

[0022] As shown in figs. 3 - 5, said filling unit 17 receives the product from the line 11 and delivers it via the pipe 10 to the interior of the tube of packing material 8.

[0023] According to a known way, a sealing device (not shown) is positioned around the feeding pipe 10, made e.g. of flexible material, and rests against the inner wall surface of the tube of packing material 8, so as to form a tight seal. Moreover, sterile gas or air is conveyed via a. feeding pipe 18 into the space existing at the lower end of the tube tightly sealed by the sealing device above mentioned, this space being constantly held at a slight overpressure by the forced feed of sterile air or gas.

[0024] The filling unit 17 consists essentially of a pair of valve group 19, 20, between which a unit functionally useful for the filling is interposed, e.g., a metering unit such as a pump.

[0025] The first valve group 19 comprises a first valve 22 whose shutter element 23 allows selectively the communication between the line 11 and a portion 24 of a duct 25 communicating with said pump 21.

[0026] A second valve 26, by means of a related shutter 27, connects selectively said portion 24 to a chamber 28 within which via pipes 29 sterile steam is fed, such as e.g. created by a central generator 30.

[0027] A third valve 31, it too by means of a related shutter 32, connects selectively the portion 24 of the duct 25 to a pipe 33, which can be connected both to a centralized washing unit 34 and to a pipe 35 of sterile steam, by related interrupting means 36, 37.

[0028] The second valve group 20 communicates with the pump 21 via a duct 38, where a first valve 39 is provided, with a related shutter 40 for selective interrupticn towards a portion 41 of the same duct 38.

[0029] A second valve 42, by means of a related shutter 43, selectively connects said portion 41 to a chamber 44 which in its turn may be connected with or isolated from the outside, interruption means 45 and condensate discharge and/or recovery means 46 being provided. A third valve 47 connects selectively by means of a shutter 48 the pipe 10 to the portion 41 and to a further pipe 49 for feeding a sterilizer gas to the pipe 10.

[0030] The valve 42 constitutes with its mower seat the border between the aseptic filling unit and the packing machine.

[0031] The valve 47 belongs to the packing machine and the movements thereof are dictated by the machine operating programme.

[0032] Also the shaft of the pump 21, together with its relating sealing elements, are submitted via the pipe 29 to sterile condensate generated in a condenser 30.

[0033] An aseptic filling unit provided according to the present . invention is during its normal operating in the condition as shown in fig. 3, and the product follows the path as identified by the full line arrows.

[0034] For this to be possible, in the first valve group 19- the shutter 23 is retracted and allows the connection between the line 11 and the portion 24 of the duct 25, whilst the shutters 27 and 32 are in their closing positions of the chamber 28 and of the duct 33.

[0035] In the second valve group 20 the shutter 40 is retracted, and allows the communication between the duct 38 and its portion 41 communicating with the pipe 10.

[0036] The shutters 43 and 48 are so positioned, as to close the pipe 29 and the pipe 49.

[0037] The presence of the metering element or pump 21 in correspondence of each packing machine 1 allows the single containers 14 to be filled with a well predetermined dosage, even if the product exhibits a certain compactness, because of the presence of solid particles in a large quantity.

[0038] If for any particular occurrence the packing is to be stopped for the noticed lack of aseptic conditions, a local sterilizing can be undertaken of the filling unit 17 without causing any inconveniences to the line and to the other packing machines. The inlet of the product can be indeed stopped by acting on the shutter 23 of the valve 22, thus preventing the delivery from the line 11 (fig. 4).

[0039] The valves 26 and 31 are then actuated, so as to allow the sterile steam to respectively enter the portion 24 and duct 25, coming from the pipe 33 after having opened the interrupting means 37.

[0040] The sterile steam passes, following the path indicated by the point-dotted arrows, from the pump 21, from the duct 38 and, the shutter 43 having been preliminar- ly moved to close the portion 41, fills the chamber 44 and escapes out of the filling unit 17.

[0041] After having carried out a pre-heating, along the same path of the arrows of fig. 4, steam at 130 - 140°C is circulated for a certain time, so as to sterilize the whole unit. The chamber 28 is used as antiseptic seal barrier.

[0042] After that the feed of sterile steam has been stopped, by repositioning the valves and their related shutters as shown in fig. 3, the production is started again under aseptic conditions.

[0043] If then one wants to carry out a'washing stage at the end of the cycle, or if the replacement is wished of the metering unit following a changing of the product to be packed, one operates (fig. 5) so as to connect the filling unit 17 to a centralized washing unit 34.

[0044] The interrupting means 36 is open and the shutter 32 is lowered, not before having closed and isolated by the shutter 23 the unit 17 from the line 11.

[0045] The shutter 27 is then lowered to close the duct 25, thus causing the inlet of sterile steam into the portion 24 and into the chamber 28.

[0046] As for the second valve group 20, no actuation thereof is commanded, but the end of the pipe 10 is connected to the washing unit 34 to form a closed loop, after that the tube of material 8 has been removed, or through the open end of the same tube. The washing chemical liquid circulates according to the dotted arrows of fig. 5.

[0047] Such a washing is carried out by means of a suitable liquid under non aseptic conditions and it serves to re move residues, above all of solid particles, sticking on the various components of the filling unit.

[0048] After this treatment, a further pre-heating, a ste rilization and possibly a cooling, as previously described, must be carried out to the purpose of restarting the packing.

[0049] Advantageously, for replacing the metering element 21, not any intervention is necessary on the sterilizing system of the packing machine.

[0050] The installed metering element 21 is so evident, that it can be washed and subsequently sterilized without incurring danger of contaminating the sterile line 11 .

[0051] This, thanks to the presence of steam in the inter mediate portion between the shutters 23 and 27.

[0052] It is advantageous as much to note that the easy and quick dismantling of a metering element for replacing it with another element allows the single packing ma chine 1 to be fitted to the packing of products having different characteristics.

[0053] The presence of metering units of different types and adjustable as desired, makes it moreover possible to carry out a packing, with the same product, in a desired and predetermined amount, e.g., with the container completely filled, or with an upper empty space.

Claims

1. Unit for the aseptic filling of long-lasting products with fluid behaviour into containers, for packing machines of the type wherein a pipe feeds said product, outcoming from a sterilization unit, into said containers, on the machine means for sealing the said containers being provided, characterized in that it is positioned between said product feed pipe and said product sterilization assembly, it being substantially constituted by a couple of valve groups, between which a unit functionally useful to the filling thereof connected by related pipes is inserted.

2. Filling unit as claimed in claim 1, characterized in that said unit functionally useful for the filling a metering unit. is a metering unit.

3. Filling unit as claimed in claim 1, characterized in that said sterilization assembly is centralized, and said unit is insreted in a branched line on a centralized line connected to said sterilizer to the purpose of feeding a plurality of packing machines, a pump being provided for circulating the product in said line.

4. Filling unit as claimed in claims 1 and 3, characterized in that at least one of said said valve groups is connected via a pipe to a washing unit, related interrupting means being provided.

5. Filling unit as claimed in claim 2, characterized in that said metering unit is a pump.

6. Filling unit as claimed in claim 1, characterized in that eachone of said valve groups comprises a set of three valves acting selectively for allowing the passage of the product, or the passage of a sterilizing fluid element coming from a centralized cashing fluid generating unit or tank.

7. Filling unit as claimed in claim 2 and 6, characterized in that a first valve group of said pair of groups is placed upstream to the metering unit and to the related connecting duct and comprises a set of three consecutive valves, a first valve which selectively connects said product sterilization assembly to the duct towards said metering unit passing through an intermediate duct portion, it being possible to place said intermediate duct portion in communication, by actuating a second valve, with a chamber inside which a sterile fluid is circulated, a third valve closing a pipe for feeding a sterile fluid and/or a washing fluid connected to said intermediate duct portion, and to said duct.

8. Filling unit as claimed in claim 1, and 2 characterized in that a second valve group of said pair of groups is placed downstream to the metering unit and to the related connecting duct, and comprises a set of three consecutive valves, a first valve which connects selectively said connecting duct and said metering unit to said vertical product delivery pipe passing through an intermediate duct portion, it being possible to place said intermediate duct portion in communication, by actuating a second valve, with a chamber within which a sterile fluid is circulated, a third valve closing a feeding pipe of a fluid for washing said vertical product feeding pipe.

Drawing